Tremblay, M.M., Fox, M. Schnidt, J.L., Tripathy-Lang, A., Wielicki, M.M., Harrison, T.M., Zeitler, P.K., and Shuster, D.L. 2015 Proceedings of the National Academy of Sciences, 112(39), 12030-12035, doi: 10.1073/pnas.1515652112 Peter Zeitler